The transmissions consisted of repeated strings of numbers and the military alphabet code and were made famous years later when Wilco used a recording of a East German woman repeating Yankee Foxtrot Hotel Hotel Foxtrot in its breakout album (and got sued for it).

Now, it seems someone is keeping the mystery alive via the potent 21st Century combination of Craigslist and VoIP, according to Homeland Stupidity blogger Michael Hampton.

On or around May 8, the following personal ad appeared on the Internet classified ad site Craigslist. (It has since been removed.)

If you actually called the number, up until a couple of days ago you would have heard this prerecorded message (MP3). It’s a head scratcher to keep you National Security Agency analysts occupied in your spare time. Each block of numbers is repeated twice; but below I have transcribed them only once for clarity.

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